In a semiconductor device, it is preferable to form a silicide at an interface where a metal body contacts a semiconductor including silicon, in order to reduce a contact resistance therebetween. However, there may be a case where a defect such as a void or the like is generated by silicide agglomerating through a high temperature treatment performed after the silicide is formed. Therefore, the high temperature heat treatment is unable to be performed after the formation of silicide.
For example, in a semiconductor memory device, which includes 3-dimensionally disposed memory cells, a driving circuit is formed on the silicon substrate, and then, a memory cell array including a plurality of memory cells are formed. Since a manufacturing process of the memory cell array involves the high temperature heat treatment, the memory cell array would be unable to be formed, when silicides are formed in advance on gates and source drain regions of transistors that configure the drive circuit. As a result, silicides can be only formed in a contact forming process locally under a contact plug in the source drain regions of the transistors that configure the drive circuit, and there are drawbacks such as increase of parasitic resistance, and degradation of transistor performance.